The high resolution JEOL 1200 EX transmission Electron Microscope is requested along with major equipment accessories for specimen preparation and negative printing. The prupose is to establish an Electron Microscope Facility for Dental School Faculty at University of California, San Francisco. Current electron microscope facilities available to Dental School Faculty are badly outdated. Demand for an EM facility has grown over the past 5 years due to the expansion in the number of newly recruited research faculty who use electron microscopy as a major tool in their funded NIH research and the onset in the U.C.S.F. Dental School of an active program to study the oral manifestations of infection with the AIDS virus. Major areas of study by the users include: Surface membrane glycoproteins in cell-cell and cell matrix adhesion, invasion of basal lamina by tumor cells, invasive properties of placental trophoblast cells, mechanisms of adherence and invasion by pathogenic oral bacteria, oral lesions associated with infection with the AIDS virus, cytoskeletal organization in neutrophils.